Discussion On Spatial Evolution And Optimization Strategy Of Ecological Land In Downtown Chengdu Based On MSPA

Ecological space can alleviate the contradiction between ecological pattern and economic construction,and its spatial layout is necessary for the protection of natural resources and ecological environment,as well as the harmonious co-existence between man and nature.How to make reasonable planning of ecological space to meet the recreational needs,health needs,cultural needs,and portable needs of urban residents,as well as play a better function of ecosystem service value is a hot topic of current and future research and a practical problem that needs to be solved urgently.As an important core development region in southwest China,the downtown area of Chengdu is also an area with prominent urbanization phenomenon on the city scale.In this development situation,the urban built area continues to expand,and the natural urban green space and the surrounding green space cause great ecological security risks.On this background,it is necessary to conduct research on ecological space.This study takes the Chengdu central urban area designated in 2020 as the research object,obtains land use data from 1990 to 2020 and remote sensing image data from 2022,and interprets remote sensing image data using ENVI.Based on Arc GIS and Guidos Toolbox,the spatio-temporal evolution of land use pattern and ecological space pattern of ecological space were analyzed,and the main problems in the process of ecological space evolution were analyzed.Based on the new round of Chengdu territorial space planning requirements,the paper proposed to adapt to the historical background.With an ecological space optimization strategy and optimization suggestions.The main results of this paper are as follows:(1)The pattern and characteristics of land use.During the period 1990 to 2022,the ecological space land in the downtown area of Chengdu was continuously squeezed by the urban construction land space,and the cultivated land was the most occupied.The transfer of ecological land was significant,and the total amount of ecological land obviously decreased.The intensity of land use in the central urban area showed an obvious layer change structure.From 1990 to 2010,it was a high intensity development area of layer 1,and from 2010 to 2022,it was a high intensity development area of layer2.(2)Characteristics of evolution and rules of the ecological spatial pattern.The distribution of different ecological elements in the ecological space can be identified by MSPA analysis.Among them,the pore in the core area continues to decline,and the distribution shows the characteristics of centrifugal reduction.In terms of the number of core areas and pores,the core area decreased by 2762.78 km~2and the voids decreased by 86.28 km~2in 22 years.The five ecological elements of isolated island,marginal area,roundabout island,bridge area,and branch line all showed an increasing state.They increased 92.76km~2,412.85km~2,15.93km~2,462.78km~2,and 164.65km~2,respectively.From the perspective of spatial distribution,the core area and the pores showed the change law of centrifugal shrinkage,while the other five ecological elements showed the change law of centrifugal dispersion growth.(3)Based on the evolution law of ecological space and the background of territorial space planning,land use data in 2022 is selected as the research basis to identify ecological source areas,construct ecological resistance surfaces,ecological corridors and ecological nodes,and restore the connectivity of ecological space.Based on the MCR model,14 ecological source regions,30 ecological corridors,2 ecological nodes,and 5 ecological fracture points were identified.Based on ecological space optimization strategies were studied,in order to provide research basis for the ecological space planning theory and ecological space planning ideas for the territorial space planning of Chengdu.